Low-water-alarm device for boilers.



1.11. JONES. LOW WATER ALARM DEVICE POR BOILERS.

APPLOATION FILED JUNE 14, 1913.

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Patented Sept. 15, 1914.

LAWRENCE R. JONES, 0F WHEATON, ILLINOIS.

LOW-WATER-ALARM DEVICE FOR BOILERS.

Specification of Letters Patent.

Patented Sept. 15, 1914.

Application led June 14, 1913. Serial No. 773,622.

To all whom 'it may concern Be it known that I, LAWRENCE R. JONES, acitizen of the United States, residing at Wheaton, in the county ofDupage and State of Illinois, have invented certain new and usefulImprovements in YLow-Vi ater- Alarm Devices for Boilers, of which thefollowing is a specification.

My invention relates to low water alarm devices for boilers and has forits general object to provide such a device in which the fusibleelement, when destroyed in the course of the functional operation of thedevice, may readily be renewed from the outside of the boiler ,withoutpermitting needless escape of steam and without puttlng the boiler outof commission.

In the drawing wherein I have shown a single embodiment of my invention,for purposes of illustration: Figure 1 is a central vertical sectionthrough the alarm; Fig. 2 is a transverse section on line 2 2 of Fig. 1.Fig. 3 is a transverse section on line 3-3 of Fig. 1. Fig. 4 is a detailsection on line 4 4 of Fig. 1.

In the drawing 10 indicates a fragment of the boiler shell having anopening 10 therein through which is screwed from the inside of theboiler a slender' bushing 11, flared as at 12 at its lower end andhaving threaded therein a tubular casing 13. At its bottom, at thedesired elevation in the chamber and the boiler space.

with the tube to form a shoulder 17.

boiler, said casing carries one element of a valve. The valve is hereinshown as of turncock construction, and its ported shell or casing member14 has its flared rim 15 screwed onto a sleeve 16 which is screwed ontothe extremity' of the tubular casing 13,

said sleeve 16 having a reduced rim alining Screws 18 and 19- fix theshell 14 on sleeve 16, and the sleeve on tube 13. Within theshell 14intertits the taper valve 21 having its ports leading into a centralchamber 22, rotation of the valve obviously permitting or preventingcommunication between the interior The valve underlies the sleeve 16,and is adjustable in its shell to take up wear by the usual threadedstem 21 passing through the bottom of the shell and carrying nuts 25.The bottom of the chamber has therein an apex, 26, so that the bottomwalls of the valve chamber slope toward the valves.

While I have thus described for purposes of full disclosure one specificform of valve suitable for employment in the practice of my 1nvent1on;other forms of valve may be employed.

The valve for controlling communicationy between the interior andexterior of the tubular casing 13 is operated by a valve stem 27 whichextends upward through the cas- 1ng ,13 and bushing 1,1 and carries,adjacent to its upper end, a turning handle 28. The stem 27 is madehollow and is screwed and keyed, as at 29 to the throat of valve 2l, sothat the hollow stem opens into the interior chamber of the valve. Thebushing ll'carries, outside of the boiler shell 10, a suitable gland 30for tightly packing the valve stem, and on said bushing may be mounted abar 3 1 to which handle 28 may be padlocked.

Within the area of the Casin 13 oontrolled by the valve, (so that fluldmay be admitted thereto from the boiler, or excluded therefrom, byopera-tion of the valve) I arrange. the removable, fusible element whichcontrols a passage, normally closed by the fusible element, and openedto the egress of steam when said member fuses. In the specificconstruction shown an alarm tube 33 is fitted snugly within the hollowvalve stem 27, so that its lower end may protrude into the yinteriorchamber of the hollow valve, the lower end of said tube being interiorlyscrew threaded to receive the-threaded extremity of the fusible plug 35,made of -any metallic alloy adapted to fuse at the In the operation ofthe device the fusibleA plug 35 is located below the normal water lineofthe boiler and the valve is open. Should the water-.in the boiler gettoo low, so that'the plug may be attacked by the steam, the plug fusesand the escape of steam through the alarm tube, (or the operation ofanysuitable device worked by steam so escaping,) gives the alarm. The.

fused metal runs out of the valve by reason of 1ts angular bottom wall.Thereupon the valve 21 controlling communication between ioo the.interior of`the boiler and thel interior of the casing 13 may be closed,so cutting 0H the escape of steam, and then the alarm tube may beremoved from its sition and a new fusible element inserte in itsextremity and the alarm tube again inserted in place, afterwhichthe'valve may again be opened to restore all of theparts to normalcondition.

While I have herein described in some detail a particular embodiment ofmy invention. it will be apparent to those skilled in the art that manychanges might be made in the details of constructions without departurefrom the spirit of my invention and within the scope of the appendedclaims.

Having described my invention, what l claim is:

l. In a boiler alarm device, the combination of a casing extending intothe boiler to a point below the normal water level and communicatingwith the exterior through a single opening in the boiler shell, a valvewithin the boiler for opening and closing communication between theinterior of said casing and the interior of the boiler, means extendinglongitudinally through said casing for operating the valve and a fusiblemember located within the casing and removable therefrom through thecasing. p

2. In a low water alarm of the character described, the combination withthe boiler shell, .of a casing supported by such 4shell and extendinginto the `boiler below the normal water level, a valve controllingcommunication between the. interior of said casing and the interior ofthe boiler, a valve stem extending through said casing to the exteriorthereof, an alarm tube extending to a point within the casing andremovable therethrough, and a fusible element, located below the normalwater level, normally closing said alarm tube.

3. In a low water alarm of the character described, the combination of acasing adapted to be secured to the shell of a boiler, a valve at oneextremity of said casing, controlling the communication of the interiorof said casing with the interior of the boiler, a hollow valvestemextending throughl said casing to the exterior thereof, a removablealarm tube extending through the hollovv7 valve stem, a fusible membernormally closing the inner end of said alarm tube and positioned withinsaid casing, whereby the opening and closing of the valve controls thecommunication of the boiler-contained fluid with the fusible member.

4. In a device of the character described,

the combination of a tubular casing, a valve.-

casing carried by the lower end thereof, :1

Vhollow valve within said casing, a valve stem extending through saidcasing, a tube extending through said hollow valve stem and at its lowerend entering the hollow valve, a fusible plug normally closing the lowerend of said tube, a bushing adapted to engage the shell of a boilersurrounding said valve stem and engaging the casing to carry the same,packing means between the 'bushing and valve stem, a valve handlecarried by said stem, and packing means between the alarm tube and thehollow valve stem. v 5. In a low water alarm of the character described,the combination of a valve positioned within the shell of a boiler, ahollow valve stem extending through said shell to the exterior thereof,a removable alarm tu'be extending through the hollow valve stem, afusible member normally closing the vinner -end of the alarm tube andpositioned within the valve, whereby'the opening and closing of thevalve controls the communication o f the boiler contained fluid with thefusible member. v.

6. In a low water alarm of the character described, the combination of avalve casing secured within the interior of the shell of a boiler, ahollow valve seated within the said valve casing, a hollow valve stemextending through the boiler shell to the exterior thereof, a removablealarm tube extending through the hollow valve stem, a fusible membernormally closing the inner end of the said alarm tube and positionedwithin the hollow valve, whereby the opening and closing of the valvecontrols the communication of the boiler contained fluid with thefusible membei. r

7. In a low water alarm of the character described, the combination of avalve casing positioned within the shell of the boiler, a hollow valveseated within the casing, a hollow valve stem extendin through the shellto the exterior thereo a removable alarm tube extending through thehollow valve stem, a fusible member normally closing the inner end ofthe alarm tube and positioned within the valve, the lower faces of theapertures in the said valve members being tapered downward from a pointbeneath the fusible plug to the outer openings substantially as and forthe purpose set forth. v

8. In a low water alarm valve of the character described, thecombination of a valve casing, a hollow valve within the casing, ahollow lvalve stem extending to the exte rior of the boiler, a removablealarm tube `within the hollow valve stem, and a removable fusible membernormallyv closing the inner end of the alarm tube and positioned withinthe hollow valve, the lower walls of the valve passages being taperedaway from a point beneath the fusible plug to permit the gravitationaliow of the fused plug away from the valve parts and prevent theirobstruction.

9. In a low water alarm, the combination of a valve positioned withinthe shell of a boiler, a hollow valve stem extending through said shellto the exterior thereof,

-a removable alarm device extending through the hollow valve stem, and afusible member carried at the inner end of the alarm device, whereby theopening and closing of the valve controls .the communication of theboiler contained uid with the fusible member.

10. In a low water alarm of the character described, a casing adapted tobe secured to the shell of a boiler, a valve at the extremityy of saidcasing, controlling the communication of the interior of said casingwith the interior of the boiler, means extendin through said casing tothe exterior thereo cation of the boiler contained fluid with thefusible member.

In testimony whereof I hereunto set my hand in the presence of twowitnesses.

LAWRENCE R. JONES.

In the presence of- Gno. T. MAY, Jr., MARY F. ALLEN.

